The upstream spill closed Lake Accotink in Springfield out of an abundance of caution, the Fairfax County Wastewater Management Program announced.
"Out of an abundance of caution, immediate closure of lake activities is recommended for activities involving contact with the lake, such as swimming and fishing, as the water may be contaminated," the department said.
Bacterial testing of the water is underway, and results were expected to be released Saturday, July 1.
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